[1] An island is land surrounded by water. It is usually separated from the mainland by at least 2 kilometres and measures between 0.15 and 2.2 million square kilometres. Islands in the ocean are categorized into high and low-lying islands, land surface area, continental or oceanic, habitation, population, by their distance to the continent. Continental islands are those that separated from the mainland and oceanic islands are those that rose from the sea as volcanic or coral deposits.
[2] Islands are rich reservoirs of animal and plant species. The islands with biodiversity most at risk are oceanic and small islands. Islands have unique biodiversity that is distinct from that found in continental land mass areas. Flightless species, dwarfism and gigantism are some unusual characteristics.
[3] Some island species are found nowhere else apart from these areas – we call them endemic species. Isolation, island size and landscape diversity determine the level of endemic species found. Madagascar boasts the greatest number – 8000 – of endemic species in the world. The greatest percentage of endemic amphibian species is found in Seychelles. Another island, Cuba, has 18 endemic mammals.
[4] The population of islands is 600 million. This population depends on many of the resources of their island environment. The ecosystems of islands provide fresh water, wood, fibre, food and raw materials as well as cultural resources for economies and lifestyles. They also supply natural defence, contribute to climate regulation, and provide the world with resources and commercial agriculture, fisheries, and tourism. However, island economies are more vulnerable due to the smaller population, distance from larger markets, environmental threats, fragile ecosystems, dependence on other markets and a weaker institutional capacity.
[5] Despite endemic species and vast biodiversity, islands are still at risk. This is due to the fact that species are low in numbers, putting them at risk of extinction. Because there is less competition among these species, they have developed survival strategies based on interdependence and coevolution. Consequently, many species on islands are very rare and endangered. Extinction is on the increase. As an example, 90 percent of bird species that are now extinct were island-dwellers.
[6] The Report of the Global Conference on the Sustainable Development of Small Island Developing States explained that the biological diversity of island ecosystems is endangered, vulnerable, isolated and fragile. It was also noted that biodiversity loss would accelerate and continue, due to pollution, climate change and exploitation of island areas. Some threats to island biodiversity include tourism, invasive alien species, climate change, natural disasters, unsustainable behaviour and pollution. Work plans have been outlined recently to address these challenges confronting island populations. In 1992, Agenda 21 established activities for sustainable development in these regions, through education, technology, data and strategy along with the cooperation of the international community in the support of endangered regions.
[7] The Barbados Programme of Action (BPoA) for the Sustainable Development of Small Island Developing States was produced in 1994 by the United States. It addresses the core issues of sustainable development, calling for action in 14 priority areas. These actions include the conservation of biodiversity, the supply of education, the creation of gene banks, and studies on biodiversity. It also includes NGO contributions in the areas of indigenous group protection, site protection from alien species and better access to financial and technical resources. These developments have clearly led to a greater awareness of both the value of these precious areas and our obligation to protect them from further risk.
